This research will seek to measure the effect of adding a method to reduce the impact of stress to a cardiac rehabilitation program. Three problems will be addressed: Does the use of relaxation therapy enhance the outcomes of a rehabilitation program for Post-MI patients? Is the overt behavioral style (Type A vs. Type B) of an individual related to the rehabilitation outcomes? Is the effectiveness of relaxation therapy related to the overt behavioral style of the individual? A quasi-experimental design will be used. A sample of at least 60 Post MI patients will be drawn from an on-going cardiac rehabilitation program. They will be stratified according to overt behavioral style, as measured by the Jenkins Activity Survey, and the experimental group will be taught Benson's relaxation technique in addition to the regular components of the program. The control group will receive the regular program which does not involve a specific relaxation technique. To determine the efficacy of the addition of the relaxation technique, the subjects will be measured at intervals on blood pressure; heart rate; activity level (MET level); and health status, as measured by the Sickness Impact Profile. To test the hypotheses, two-way repeated measures analyses of variance will be calculated for each dependent variable. This study seeks to determine if a simple, cost free method of stress reduction will have an effect on the rehabilitation of individuals who have had a myocardial infarction. The possible benefits include reduction in morbidity and mortality, reduction of health care costs, and improved quality of life for these individuals.